1. Field of the Invention
The present invention relates to an exhaust purifying apparatus in a saddle-ride type vehicle such as a motorcycle or a buggy car. More particularly, to an exhaust purifying apparatus that supplies secondary air to an exhaust system of an internal combustion engine to purify unburnt components in exhaust gas.
2. Description of Background Art
For example, JP-A No. 2002-227641 (FIGS. 1 to 4) disclose a secondary air that is supplied to an exhaust system of an internal combustion engine in order to reburn unburnt components in the exhaust gas even in a saddle-ride type vehicle such as a motorcycle or a buggy car, against exhaust gas regulation.
As disclosed in JP-A No. 2002-227641 (FIGS. 1 to 4), in a motorcycle with a power unit, the other side of a secondary air supply pipe of which one side is connected to the exhaust system (in an exhaust port) of the internal combustion engine is connected to a secondary air control valve and a secondary air filter is connected to an upstream side of the secondary air control valve.
In addition, an air suction pipe at an upstream side of the secondary air filter extends to a vehicle rear end along an upper side of a main frame of the motorcycle and an inlet port is opened at the rear end.
In an exhaust purifying apparatus that has a secondary air control valve and a secondary air filter, outdoor air is sucked from an air suction pipe at an upstream side of the secondary air filter, and supplies the outdoor air as secondary air to an exhaust system. JP-A No. 2002-227641 (FIGS. 1 to 4) discloses that a storage box and a fuel tank which are parallel to each other in a forward and backward direction of a vehicle are installed on an upper part of a main frame below an occupant seat, and the secondary air control valve and the secondary air filter are installed between the storage box and the fuel tank at the right side and the left side of the vehicle, respectively, and as a result, a pipe connecting the secondary air filter and the secondary air control valve is installed horizontally between the storage box and the fuel tank.
Further, the air suction pipe positioned at the upstream side of the secondary air filter extends at the right side of the vehicle between the storage box and the fuel tank and thereafter, extends to a vehicle rear end along an upper part of a right main frame of a motorcycle and an inlet port is supported on the main frame while being covered with a breathable sponge damper at the rear end.
As a result, the height of an occupant seat is increased due to the placement of the pipe to increase the size of the vehicle and further, when the increase of the height of the occupant seat is suppressed, the position of the main frame is lowered to restrict a vertical swing amount of a power unit.